The present invention relates to a liquid jetting head, such as an ink jet-type recording head, and more particularly to a liquid jetting head having a head unit, which is capable of jetting liquid contained in a liquid containing chamber from nozzle orifices by driving pressure generating units, and a driving substrate, which supplies the pressure generating units with a driving signal.
A representative of a liquid jetting head which can jet (discharges) liquid may be an ink jet-type recording head (hereinafter, referred to as recording head) which is mounted in an ink jet-type printer (a kind of liquid jetting apparatus, hereinafter referred to as printer) which performs a record by discharging ink in a liquid state and striking a recording medium (a jetting object), such as recording paper with the ink. Further examples of the liquid jetting head include a color material jetting head used for manufacturing a color filter of a liquid crystal display, an electrode material jetting head used for forming electrodes of an organic electro luminescence display (organic EL display) and a field emission display (FED), and a living organic substance jetting head used for manufacturing a bio-tip (a biochemical element).
The liquid jetting head includes a driving substrate (printed board, circuit board) which receives a driving signal from an apparatus main body and supplies the driving signal to pressure generating units. The driving substrate is provided in a case member. In the liquid jetting head, the driving signal is supplied to each of the pressure generating units from the driving substrate via wiring members having flexibility (hereinafter, referred to as flexible cable), such as tape carrier package (TCP) (refer to seventh page of Patent document 1). Further, a terminal portion which is located at an end of the flexible cable is connected to a terminal portion of the pressure generating unit, and the other terminal portion which is located at the other end of the flexible cable is connected to a substrate terminal portion provided on the driving substrate.
In the structure disclosed in Patent document 1, the pressure generating units (vibrator units) are received in a receiving space formed in the case member, the driving substrate is arranged so as to cover an upper opening of the receiving space while being disposed in parallel with a nozzle formed-surface, and an introducing needle unit is attached to the case member in the state in which an driving substrate is interposed between the case member and the introducing needle unit. That is, the liquid jetting head is structured in a manner such that the driving substrate is provided with a through-hole having a size as large as the flexible cable can pass therethrough and wiring between the driving substrate and the pressure generating unit is accomplished by the flexible cable passing through the through-hole. That is, an end of the flexible cable with the other end connected to the pressure generating unit is connected to the driving substrate by a soldering method in which some solder is pulled to pass through the through-hole and then bent toward a connection terminal formed-surface of the driving substrate.
However, in the case in which the driving substrate is provided with the through-hole, wiring patterns must be formed on the driving substrate so as to detour around the through-hole. For such a reason, a size of the driving substrate in a plan view increases, resulting in a large driving substrate. As a result, a problem, in which the entire volume of the liquid jetting head increases, arises. In these days, line-type heads, in which a plurality of liquid jetting heads are incorporated in a body to jet liquid to a large area at a single time, are put to practical use. Accordingly, it is expected that the liquid jetting head progresses in downsizing when considering application of the line-type head to the liquid jetting head.